Thecacera sp. 3

Koh Racha Yai, Phuket, Thailand
Photo courtesy of Lawrence Neal
Depth 26 meters

Thecacera sp. 3 undescribed


This particular undescribed Thecacera species is well-known among the local Thai divers as the "Pikachu Nudi" after the Japanese cartoon character, which has a similar orange-and-black colour scheme and whose long ears resemble the Nudibranch's floppy extra-branchial processes. It may be Thecacera sp. 3 in Indo-Pacific Nudibranchs and Sea Slugs, but that's open to debate.

This Andaman Sea species has a translucent body with bold orange and black spots dotted all over, including on the gills, and orange rhinophore tips. It gets up to about 25 mm in length. Thecacera sp. feeds on arborescent (tree-like) bryozoans which form small clumps on current-swept sand slopes at depths over 20 metres. The pale pinkish-orange bryozoans resemble little parasols that flop about in the current, giving photographers a frustrating time.

In Thailand, this Thecacera species can often be found in the sandy areas around Racha Yai Island off Phuket and also off the Phi Phi Islands. Generally, if the bryozoan prey is around there's a good chance the Nudibranch will be too.

Lawrence Neal
Bangkok, Thailand
July 2012

Lawrence at Tulamben, Bali, Indonesia with
Agung Volcano in background

Lawrence is a newspaper journalist based in Bangkok, Thailand. He escapes the office as often as he can to go diving in the rich waters of the Indo-Pacific but his regular dive sites are just down the road at Pattaya. The vis is usually pretty appalling and the diversity nothing like as rich as hotspots like Lembeh or Anilao, but, in his words, "that's what makes it challenging and fun".

Lawrence uses a Nikon D200 in a Nexus housing with a housed Nikon SB800 Speedlight, Inon Z240s or some combination thereof. At Pattaya his lens of choice is the 60 mm macro, "the water is much too murky for anything longer".

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